This invention relates to a rolling bearing for longitudinal movement between a shaft and a housing or the like, wherein a plurality of endless rows of rolling elements are distributed about the circumference of the bearing, and wherein the bearing has separate rails for receiving the loads of each of the rolling elements rows.
Rolling bearings of the above type are disclosed, for example, in co-pending U.S. application Ser. No. 821,472 filed Aug. 3, 1977, now U.S. Pat. No. 4,138,167. In this type of bearing one side of the rails have convex curvature in the lengthwise direction, and the opposite sides of the rails are straight in the lengthwise direction. The rails are arranged in the rolling bearing with either their straight side, or with their convex curved side, directed radially outward in the cage shell. The straight sides are directed radially outwardly for use in a precision machine, so that the straight sides closely engage the inner surface of the bore of the housing throughout their extent, to prevent tilting movement of the rails. Alternatively, the convex curved sides of the rails may be directed radially outwardly to engage the inner bore of the housing for use in a less accurate machine, wherein a determined adjustability or tiltability of the rail is desired between the rails and the housing. In this type of bearing, in the event of wear or the appearance of fatigue (i.e. damage due to fatigue of the materials), the rail in use must be substituted by a new unused rail, for continued use of the bearing. This results in a limit on a useful life of the bearing and the useful life of the rail.